Production banners Warner Bros and DC Entertainment are reportedly developing a movie focusing on Harley Quinn and The Joker. Both Margot Robbie and Jared Leto are set to reprise their respective roles in the movie which has a title of 'Harley Quinn vs The Joker'. Both Quinn and Joker are villains and part of 'Suicide Squad'. The yet-to-be-confirmed project seems to be in addition to 'Suicide Squad 2', which has Jaume Collet-Serra as the top choice to direct, and the in-development 'Gotham City Sirens', which has confirmed the return of Robbie as the pig-tailed super-villain with David Ayer on board to sit behind the camera. The new project is described as a 'Suicide Squad' spin-off and DC Entertainment President and CCO Geoff is set to produce.
Source: IANS